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Objective: Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) have been shown to accumulate in the human body. The purpose of the present study was to examine the factors associated with the blood levels of PFOS and PFOA., Methods: A cross-sectional study was performed on 307 men and 301 women (aged 16-76 years) living in 15 prefectures in Japan. Blood levels of PFOS and PFOA were measured by liquid chromatography-mass spectrometry. Hepatic enzymes (γ-GTP, GOT, and GPT) and ω-3 polyunsaturated fatty acids (DHA and EPA) levels in serum were also measured. Associations between the levels of PFOS and PFOA in blood and the intake frequency of 41 kinds of dishes, foods and beverages and the serum levels of liver enzymes and ω-3 polyunsaturated fatty acids were examined using rank correlations., Results: Frequency of intake of boiled fish in broth, sliced raw fish and coastal fish showed significant positive correlations with PFOS concentrations in blood after adjustments for potential confounders. Serum levels of GOT, GPT, DHA and EPA showed significant positive correlations with PFOS and PFOA in blood. There was also a significant regional difference in the blood levels of PFOS and 2013PFOA, with medians being highest in the Tokai/Hokuriku/Kinki region., Conclusions: These findings suggest that the concentrations of PFOS in blood were mainly associated with fish consumption and that the levels of PFOS and PFOA were associated with the serum levels of liver enzymes in Japanese populations. Further investigations are required to clarify the reason for the regional differences in blood levels of PFOS and PFOA in Japan.

Rationale and Objectives: An atlas-based automated liver segmentation method from three-dimensional computed tomographic (3D CT) images has been developed. The method uses two types of atlases, a probabilistic atlas (PA) and a statistical shape model (SSM)., Materials and Methods: Voxel-based segmentation with a PA is first performed to obtain a liver region, then the obtained region is used as the initial region for subsequent SSM fitting to 3D CT images. To improve reconstruction accuracy, particularly for highly deformed livers, we use a multilevel SSM (ML-SSM). In ML-SSM, the entire shape is divided into patches, with principal component analysis applied to each patch. To avoid inconsistency among patches, we introduce a new constraint called the "adhesiveness constraint" for overlapping regions among patches., Results: The PA and ML-SSM were constructed from 20 training datasets. We applied the proposed method to eight evaluation datasets. On average, volumetric overlap of 89.2 +/- 1.4% and average distance of 1.36 +/- 0.19 mm were obtained., Conclusions: The proposed method was shown to improve segmentation accuracy for datasets including highly deformed livers. We demonstrated that segmentation accuracy is improved using the initial region obtained with PA and the introduced constraint for ML-SSM.

The present paper describes a method for intraoperative recovery of respiratory motion and deformation of the liver by using a laparoscopic freehand 3D ultrasound (US) system. The proposed method can extend 3D US data of the liver to 4D by acquiring additional several sequences of time-varying 2D US images during a couple of respiration cycles. 2D US images are acquired on several sagittal image planes and their time-varying 3D positions and orientations are measured using a miniature magnetic 3D position sensor attached to a laparoscopic US (LUS) probe. During the acquisition, the LUS probe is assumed to move together with hepatic surface. Respiratory phases and in-plane 2D deformation fields are estimated from time-varying 2D US images, and then time-varying 3D deformation fields on sagittal image planes are obtained by combining 3D positions and orientations of the image planes. Time-varying 3D deformation field of the volume, that is, 4D deformation field, is obtained by interpolating the 3D deformation fields estimated on several planes. In vivo experiments using a pig liver showed that the proposed method could perform accurate estimation of respiratory cycle and in-plane 2D deformation fields. Furthermore, evaluation for the effects of sagittal plane interval indicated that 4D deformation fields could be stably recovered.

An atlas-based automated liver segmentation method from 3D CT images is described. The method utilizes two types of atlases, that is, the probabilistic atlas (PA) and statistical shape model (SSM). Voxel-based segmentation with PA is firstly performed to obtain a liver region, and then the obtained region is used as the initial region for subsequent SSM fitting to 3D CT images. To improve reconstruction accuracy especially for largely deformed livers, we utilize a multi-level SSM (ML-SSM). In ML-SSM, the whole shape is divided into patches, and principal component analysis is applied to each patches. To avoid the inconsistency among patches, we introduce a new constraint called the adhesiveness constraint for overlap regions among patches. In experiments, we demonstrate that segmentation accuracy improved by using the initial region obtained with PA and the introduced constraint for ML-SSM.

This paper describes a rapid method for intraoperative recovery of liver motion and deformation due to respiration by using a laparoscopic freehand 3D ultrasound (US) system. Using the proposed method, 3D US images of the liver can be extended to 4D US images by acquiring additional several sequences of 2D US images during a couple of respiration cycles. Time-varying 2D US images are acquired on several sagittal image planes and their 3D positions and orientations are measured using a laparoscopic ultrasound probe to which a miniature magnetic 3D position sensor is attached. During the acquisition, the probe is assumed to move together with the liver surface. In-plane 2D deformation fields and respiratory phase are estimated from the time-varying 2D US images, and then the time-varying 3D deformation fields on the sagittal image planes are obtained by combining 3D positions and orientations of the image planes. The time-varying 3D deformation field of the volume is obtained by interpolating the 3D deformation fields estimated on several planes. The proposed method was evaluated by in vivo experiments using a pig liver.

In order to examine the primary structure of acetoacetyl-CoA synthetase (acetoacetate-CoA ligase, EC 6.2.1.16; AA-CoA synthetase), the cDNA clone encoding this enzyme has been isolated from the cDNA library which was prepared from the liver of rat fed a diet supplemented with 4% cholestyramine and 0.4% pravastatin for 4 days. Nucleotide sequence analysis of cloned cDNA revealed that AA-CoA synthetase of rat liver contains an open reading frame of 2019 nucleotides, and the deduced amino acid sequence (672 amino acid residues) bears 25.0 and 38.9% homologies with acetyl-CoA synthetases of Saccharomyces cerevisiae and Archaeoglobus fulgidus, respectively.

In order to investigate the physiological role of acetoacetyl-CoA synthetase (acetoacetate-CoA ligase, EC 6.2.1.16), a cytosolic acetoacetate-activating enzyme, the effects of animal development on the activity and content of the enzyme were examined in rat liver. In male rats, the enzyme specific activity increased 21-fold at 4 weeks of age from that at 2 weeks of age, and then gradually decreased, while in female rats, it increased similarly to that of male rats, but further increased, reaching a maximum about 3-fold higher than that of male rats, at 6 weeks of age. The developmental patterns of the enzyme content correlated with that of the enzyme specific activity. These results indicate that changes in this enzyme activity and content during the developmental process might influence the rate of ketone body utilization for the formation of physiologically important lipidic substances in rat liver.

Recent studies have revealed that animals have evolved a wide range of protective systems against the deleterious effects of LPS, but the molecular mechanisms in the barrier functions of liver against enterobacterial LPS, particularly in mammals, are poorly understood. In this study, we extracted a soluble fraction from the liver of normal mice (normal liver extract, NLE) and examined its effect on biologic activities of LPS. Preincubation of NLE and LPS suppressed serum-dependent TNF induction (TNF-triggering activity) of LPS; the effect was dose-dependent and overcome by increasing LPS concentration, but treatment of macrophages with NLE showed no effect. Separation by ultrafiltration and protease sensitivity demonstrated that the factor(s) in NLE was a protein(s). We tentatively called this liver LPS-inactivating factor (LLIF). LPS inactivation by LLIF was temperature-dependent and required the coexistence of divalent cations. LLIF also suppressed a synthetic lipid A analogue, ONO-4007. Pretreatment of LPS with serum rendered LPS refractory to the action of LLIF. However, LLIF was unable to inhibit limulus amebocyte lysate activation by LPS. Direct interaction of LLIF and lipid A was evident by the method of [1-14C]ONO-4007 binding to solid-phase LLIF, but treatment of [1-14C]ONO-4007 with LLIF generated no degradative products. These results suggest that LLIF probably interacts with the lipid A portion of LPS and interferes with the association of LPS and LBP (LPS-binding protein) in serum, and that LLIF may be one of the protective molecules in liver against the gastrointestine-derived LPS.